Removable blade shears



Nov. 9, 1943. E. L. RASMUS SEN REMOVABLE BLADE SHEARS Filed May 11, 1943l nventor EDWARD L. frASMUSJ'E attorney sult such root blade portionsPatented Nov. 9, 1943 f 2,333,740 i I I Edward L. Rasmussen, nearp'settle; Wash; .d pplicaticnMa y 11, 1943; Seri a1 No:4 86396 12 Claims.

I This invention relates to: a removable blade construction for, shearsand similar instruments, and .is particularly useful inshears suchasused for grass cutting, pruning and similarpurposes. lIhemost effectivecutting regionof shears is that :nearest the pivot interconnecting theshear blades: because the. greatest leverage is available on 5 such;blade portions and usually they operate in the best shearing contact,Consequently/such blade portions are used to a vgreats-gr extent thanportions farther toward the bladetips. As a rebecome dull more quickly;and yet,, because of their overlapping relationship. access ,to theseparts of theblades for sharpening purposes] is the most difficult. a l vIt istherefore a principal o jectofhmy inven tion to'provideablade'constructionffor shears which affords access to the cutting edgesoi the blades throughout their entire length so tha t they can besharpened easu an in particular this object is accomplishedby' enablingthe portions of the bladesv including th-cutting edges toybejseparatedfrqm the'restof'the blade assembly for sharpening purposes.Suchportioln ofseach blade maybe removed independentl that of the otherblade and: without requirl that the pivoted portions or thev bladestructure be v disassembled, although the removable blade portions willbe held, securely in place while the shears are being used for normalcuttingcpera tions. v An additional object is to enable a removableshear blade: holder to stifien and hold the blade securely for efiectiveoperationiin use, but to be fabricated economically jfrom"aminimum quantityofmaterial. v In, particular it is an object of my shearsficonstruction to facilitate setting of the removable blades accuratelylandsecurelyin their-respective blade holders, so'that they will cooperateproperlyfiuring use of the shears, and yet'to' permit the bladesto beexpelled positively, quickly and easily from theirholderswhen-'itisdes'ired to remove them for sharpening or replacementPurposes. 1 3 s p .1 Other advantagesof mywinvention which-are obtainedby thefmore specific'structural features offmy removable blade and bladeholding mechanism will beuiidzrstoddfrom the followingTparticulardescription of a representative embodi- 50 ment of my invention ;Forillustrative purposes my removable blade construction has been} shownasincorp'orated in shears primarily inte'nde'dfor grass cutting, but it"will be understood; that shears orthis general type may be used for.other e of grblade inserting tool (cliccgzsor l purpose tl etprinciplesof my invention may b adapted to Shears of quitedifferent construc- I lum" p v 3 gaEigure ,1 is a top perspective view of grass shearsincorporating my removable bladeostruc Eigure 2 is a top p15 assemblyillustrated in a top plan view of the bladeit self removed jromtheholder of IFigure 2.

I v Figure is a cross sectional viewtaken one the line; 4-54 of,Figurel, showing the application to 3 the removable blade Figure 5 is a crosssectional and blade holder.

yiewsimilarto Figure 4, but illustrating the application of a difierentblade inserting and removing tool; o the blade arid holder assembly. F'igurefi is a iragmentary transverse, sectional view,taken inahorizontal planev above th'e pivotedends of the blades, showing partsbroken away. a

tion is applied in the drawing ]areisirrii1a1"to these disclosed in my iPate'rntl'No. 1,941,71 issued Jan. 2, 1934.. Ins1ichshears thebiades Iare oscillated about a pivot' 2 which is received in apertures2l'iifthebladeholding plates 20 car rying the blades prepeir. "Themovable handle 3 swingsrelative .tothe fixed handle] in a planeperpendicular to the blades I, and vabout a pivot exte din transverselyof pivot-2 at'its upper end.

A rose an, integral with'the forward'end or the handle 3,h"as,en"d'sturnedtoward the blade holderslfl approximately perpendicular to themov- I I blades past each other for cutting;

The heel portions 23* of the blade holders an overlap, and theirportions encirclingethe pivot japerturesjiii are dr wn closely togetherby the securingthe' pivot in place. "In order to hold the cuttingedges'ofth blades [in contact these heel portions may be urged apart in adirection perpendicular to the blades and holders by a ball one bladeholder -.separate from the shears .Figilrei a d F ure 3 rehearse: thegeneral typefto which the re movable blade construction or my presentinvenithe direction to acetate 12;;

24 interposed between the heel portions of the purely by friction inthis manner a problem arises two homers and irecelved mwardly facmg I asto how the blades may be forced fully into the grooves 25 formed m themWhlch are prefelaflqlyv blade holder channels to seat on the channelbotso w t arcuate, t center 9 such are toms. If pressure is ap liedagainst the cutting cldlng wlth the axis of the piv t Not only 6 edge ofa blade for this purpose it will be dulled does Such ban create a Wedgmgactlon to Press to a greater or less extent. Also when the blade thecutting edges of blades I toward each other has thus been forced as faras possible into the but it holds the heel portions 23 of the bladeholdchannel the edge of th bl d projecting beyond ers apart sulficlentlythat they cannot rub the edge 21 ofthe wider channel side isinsuffiagalnsteach other, .thus constituting an anti- 10 Gem ktuafiomgafirm gripcfor withdrawing t FE St yf'orfithes hmders as? it mus in bladee dg'ewiseirrcm the time: illb'reever it is g ooves diflicult to ras athin, smooth blade firml and The blade ltself? m of hlgh grade Steelp'articularl? wiifhout risk of bending it or in j uring and can befairly thin, since the holders?!) conitscuttmg edge siderably increasethe stiffness of the "blades; 15 fl blade t b inserted into and 'I heseholders themselres can be made of rela a oveu fromrthfi quickly andeasily 1 t ve y low grade mat 1, p a the bl S fi 1 vide a keyhole shapedaperture 29 in each blade preferably of generally tnangula'rshape'ltapermg" holder, and-a eolhblemental keyhole aperture l2 m a wldem' to the pivot z-SPP W?" in each blade. The circular portions ofv thesetlally to a polnt at'the tip of the blade. As shown 2 complement-a1apertures n and 29 are vof bln'F gures 4 and -5, the thickness of thebladeis a m yzm t gm z l dit y amglogateflijeluniform throughout itswidthy'as wellu 'as its p it g ig urg mm r mspgctm, length. The bladeholder 20, which is of chan ;ifih;a. ;Wh=nl't}fe'ib1aflei@dg@ msg'z atgumm nelshape terms a pocket closed at both lerids n bt tc n'rl 1 c if'holder *2,

for reoeption tif the bl'a'de and'the latter- 1s a a 2 l r! 25 1h r0 erdis sltlenelehthwise of theholder,the v l m et l l 99 591cm by mctlpncir lil r port i ns ef the 'twb "eeiiturestwllli m ii xi thw with the Perablybe eiraetlyin -reg'istt y ias' shown in mgum" I. side facesof-the' blade itself. Eachsucwh'older kwith thip azrtstiriithisitirfthnbchsmmm i.

its fi e e andthemnerewan Of the'ihcflintothe ehahnel', tit tne tanearrc sedate;

. low bead 26' 'fo rmsithe bottom of suhQl-llrlnelmtgadispogd;iniSuchireltmnsmprlgngthmseEm latterelientithe"slletflntalof'whiohltheiblad'e i I a al a nserted thrlightly-apertures and elrl der K I 15 made W111 lemme that aaiit ine e re'es' i 'the'cha'rln'elmaybesplfead'sligl'itly 'for refception 7 cftnefledee or blade I. irtneichannerw dtn and r tta, uifibladethicknssarethus n'rdp'cit tnedywh n'the 5 g m d Gyms so atladeiisi'inser'tedas farasgi ss tleflintd necnan: e fi g 1 a'neitns'ncldetwill"resiliently'e li t eti fir 2" y g g- ,ly, so that itcannot work lcoserr'oln'tliehcrder PP P Ha w"With't'hebladei'thiisheldsnug f l f f fi ii we a O1-I"-uefit-uambingaicfion To beln-reelstryit t .BM??? :accuratel-y; iln{:cu necessary tc 'pin te- Preie abl it-hls:le tmr lentots tether orotherwiseirrtercdnnect the=blalde= an meme-intoifllegbladfiiholdelzlfiqlmfi f sonfileli 'theholder positi'ifelydn anytvayt I greater:ierce-thantthent v mentunt rtbt m '"W'hen the tjla esare he d in the bl'aide holdrs its rseitnatitlieiicladewvilrbqiplempedvfllfmbtm the twosides of they; blade holder as explainedabOVer ,l 1f During use it is probable that the accumulation of dirt andother foreign;materialibetween the blade and the sides of thebladeholder. will tend to make the blade stick in place-,1so that it-wouldbeivery diflicult to remove itby astraight pull.

With my arrangement, however-, iitislagain merely necessary toinserttinto the registering circular portions cfapertures l2 and29 thetapered-flat tool F ofFigure 5, and to drive it downward. Re-

acting between the curved edges'of the apertures l2 and -29opposite-their notches the tool will from the holder.

' It will ben'oted that the"blade"holders,' interconnected by the pivot2, are -identical, and that their narrow sides overlie those facesof theblades which overlap during a cutting operation. The edges '28 of suchnarrow blade holder sidesare 'set back sufiiciently to afiord plenty ofclear ance for movement of the cutting edge fofthe opposite blade. Bymakingthe side of the channel holder "engaging one side of eachblade"rela-' tively wide, the thin blade is adequately supported bothlengthwise and; transversely. 'Also .while I have shown the blades tubeof identical, generally triangular shape, other shapes ablefor shears ofsome types.

Although both apertures l2 and 29 arep-referaibly of keyhole shape, itwill be understood that com plemental apertures of other shape'couldbcused; Thus, for example, two parallelslots could be provided in eachblade and blade hoIden-eXtending transversely'of them in suchdocationthat one pair "of overlapping slots could "be wedged toward registry byato'olf-F to pres'slthe blade fully into the blade 'holden, whil the*otheripair' of slots could be forced toward registry to "start movementof the bladeoutoftheholder. Alternatively two pairs-of circularapertures toreceive a tool R wouldr serve the same purpose. I

' Various other departures from the preferred embodiment of my inventionshown may alsoj be made by" those skilled in the art while still' util-"izing its salient features "as defined in the appended claims. verydesirable that the blade and holder apertures, or parts thereof, be ofthe same shape and approximately the same size, so that when the bladeis properly seated in the holder theregistry of the apertures willafford a reliable indication that the blade is adjusted accurately bothlaterally and lengthwise of the holder for cutting operation. It willthen be held firmly in such position without requiring bolts, pins orother securing elements which might become loose and allow the blades tomove out of their proper cutting relationships.

What I claim as my inventionis;

1. A cutting implement comprising a blade holder of channel shape, ablade having an edge adapted to be inserted in the blade holder channel,said blade and blade holder both having apertures therein, portions ofwhich are adapted to be moved toward registry coincident with movementof said blade farther into the channel may be more 'suit- Whatever shapeis useds-"it' is of said A blade 'holder' by .a' :Iorce reacting betweenanedgel of one such aperture in one'of said mm--: bers andthe'oppositeedge oftthe other aperture; -2.- A cutting implement comprisingJa bladeholder of channel shape, a;1bladehaving anedge adapted tobe inserted-{inthe 'blade holder chan nel, said bladeand holder-both having aperturestherein of keyhole shape, the circular-portions of'which apertures areadapted to be moved toward "registry coincident with movement of saidblade farther into the channel of said blade holdertbyva force reactingbetween the edges of the circular: portions of such apertures, and thenotches of such aperturesextending in opposite directions transversely,of the 'blade and blade row side of substantially uniform widththrough-- outi-the major portion of itslength, and a wide side for onlyslight projection therebeyond of the cutting edge of a blade having itsopposit edge seatedinthe bottom of said channel pocket,-said blade andthe wider side of its blade holder pocker having apertures ttherein;portions of whichare adapted to be movedtoward registry'lcoincident withmovement of said-blade farther into the ibladeliholder pocket by a forcereacting between an edge" of one such aperture and theopposite edge ofthe other aperture.

4. A cutting implement comprising a blade, a blade holder havingach'annel blade receiving pocket closed at both ends and having "thebottom of its channel form d with a tubular edge to stiffen the bladeholder. lengthwise and to press the sides "of the channel toward eachother, suchchannel pocket portion of said blade holder includinga'narrow side of substantially uniform width throughout-the major portionof its length, and awide side for only slight projection there-- beyondotthecutti'ng edgeof ablade having its keyhole shape, the circularportions of which apertures are adapted to bemovedtowardreg istrycoincident with movement of said blade farther intothe pocket of saidblade holder by a forcerreacting between the edges of the circularportions of-such apertures, and the notches Ofisuchapertures extendingin oppositedirections transversely of the bladeholder for movement;

toward registry by insertion of a fiat tool through such aperturescoincident with movement of the blades outward of its blade holderpocket.

5. Shears comprising two blad holders, a pivot interconnecting saidblade holders near one end, each bladeholder including a channel bladereceiving portion extending froma location adjacent to said pivot towardthe end of the blade holder remote from said pivot, and two blades eachhaving its edge opposite its cutting edge received in the channeledportion of its blade holder, and retained therein solely bythefrictional clamping engagement ofthe blade holder thereon, to disposethe cutting edges of the blades in overlapping relationship.

6. Shears comprising two blade holders, a pivot interconnecting saidblade holders, said blade holders being formed of channel shape andopenme toward each other, and each having the bot CERTIFICATE orCORRECTION. PatentNo. 2, 5 ,7h0. November 9, 19M.

EDWARD L. RASMUSSEN.

It is hereby certified that error appears inthe printed specification ofthe above numbered patent requiring correction as follows: Page 5,second colu'mn, line 59, claim 1+, for "blades" read --b1,ade; page 14,first column, line 59, claim 9,-for "on" read --in-; and that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

Signed and sealed this 25th day of January, A. D. 1914-11..

. Henry Van Arsdale, (Seal) Acting Commissioner of Patents.

